Any material, including fabric, has a complex of consumer properties that depend on many indicators: the purpose of the material, the properties of the fibers and threads in its composition, the methods of production, the structure and nature of the finish, etc.

All consumer properties of fabrics can be divided into several groups.

Mechanical properties of fabrics

The mechanical properties of tissues are understood as the ability of the tissue to withstand various mechanical influences. This group includes strength, wear resistance, crease, stiffness, drape, etc.

Tensile strength of fabric. Fabrics made of synthetic fibers have the greatest strength. In general, the thicker the thread and the density, the stronger the material. In addition, the plain weave type (short overlap weave) contributes to greater strength than other weaving methods.

Wear resistance. This is the ability of a fabric to withstand various factors, such as exposure to light, sun, temperature, dry cleaning, washing, repeated stretching and contraction, sweat and moisture, etc. For example, in areas of tissue experiencing constant friction, so-called. pills, or pellets in common parlance. During repeated washes, the product is continuously stretched and compressed. Then we expose it to the sun's rays during drying, and subsequently to heat treatment during ironing. All of this naturally contributes to the loss of appearance and shape of clothing over time.

Draping. The ability of a fabric to form soft, rounded folds. Fabrics that are easily reshaped (flexible materials) are the most drapey. In turn, flexibility depends on the type and thickness of the fiber, as well as the characteristics of the structure and finish of the fabric. Fabrics made of natural silk and wool have the best drape. Slightly worse are cotton and linen fabrics. But fabrics with a large amount of synthetic fibers are the least flexible.

Physical (hygienic) properties of fabrics

This group includes hygroscopicity, air permeability, vapor permeability, water resistance, water resistance, wetness, thermal conductivity, dust holding capacity, electrification, etc.

Hygroscopicity. The ability of a fabric to absorb water vapor from the surrounding atmosphere. This indicator is not constant for the same product. It is designed to change as the relative humidity and temperature change. So, for example, the moisture absorption of clothing indoors will be less than outdoors. Clothing that comes into contact with the body should have good hygroscopicity, while for the upper layers of winter and demi-season clothing it should be minimal in order to prevent getting wet and a decrease in heat-shielding properties.

Getting wet. This is the ability of a fabric to absorb liquid droplets. This property comes to the fore in linens, towels, sheets and other fabrics.

Water resistance. The ability of materials to resist wetting. For this, their surface is treated with a special compound. At the same time, the pores of the tissue are not filled, which allows it to "breathe". It is important to know that water resistance and water resistance are not the same thing.

Waterproof. The ability of a fabric to resist both wetting and water penetration. But when processing the fabric, the pores are also filled with a special composition, which significantly worsens the hygienic properties, because air permeability and vapor permeability are practically reduced to zero. However, this characteristic is very important for raincoat and coat fabrics.

Air permeability. The ability of the fabric to allow air to pass through, thereby ensuring the ventilation of the garment and creating a comfortable moisture composition of the underwear space. It is known that a higher concentration of carbon dioxide can accumulate in the underwear space than in the air space. This can lead to fatigue and lightheadedness. Low-density fabrics have the best air permeability characteristics. The top layer of winter and autumn clothing should have low air permeability in order to protect it from cold air. Summer clothing should be well ventilated.

Water vapor permeability. The ability of the tissue to remove water vapor released by the human body into the underwear space. This is a very important characteristic for lining, linen, dress, blouse and suit fabrics. Thus, wool is the slowest to evaporate water vapor and thus has the best heat-shielding properties. But the coldest linen fabric evaporates water vapor the fastest and is ideal for hot summer.

Thermal conductivity. It characterizes the heat-shielding properties of materials: the lower the thermal conductivity, the warmer the material. First of all, the thickness of the material affects the heat-shielding properties of the material. In the pores of a thick material, there is more air with a low thermal conductivity. Therefore, the thicker the material, the warmer it is.

Dust holding capacity. This is a negative property of fabric, characterized by its ability to perceive dust and various pollution from the environment. Brushed fabrics, especially woolen fabrics, collect the most dust.

Electrification. The ability of a fabric to accumulate static electricity on its surface. As a result of friction, positive or negative charges are formed on the surface of the fabric. Negative charges, especially characteristic of synthetic tissues, can have a negative effect on the human body.

Technological properties of fabrics

Such properties can manifest themselves at different stages of garment production. In this article, we will only consider shrinkage, because the rest of the properties are more interesting for specialists in the sewing industry.

Shrinkage. This is a change in the size of the fabric due to heat or wet processing. It is especially bad if the lining fabric has a different degree of shrinkage than the upper fabric. In this case, after dry cleaning, washing or ironing, wrinkles and folds may appear on the product. Fabrics made from cellulose fibers have the highest shrinkage, and fabrics made from synthetic fibers have the least shrinkage. Some fabrics, such as silk, crepe and cotton, have a large (up to 15%) apparent shrinkage, which is almost completely restored when ironing.

When choosing clothes, you need to pay special attention to the material from which it is sewn. Each type of fabric has its own advantages and disadvantages, which determine the beauty and comfort, the duration of wear and the requirements for care.

Of course, natural fabrics have high hygienic characteristics: they let air through well, they are not hot in summer and not cold in winter, they are pleasant to the body. However, there are also tangible disadvantages. These include the rapid loss of shape as a result of numerous washes and ironing, relatively low wear resistance, and high crease. A few years ago, synthetic fabrics were not considered a worthy analogue of natural ones due to their low hygienic characteristics (especially hygroscopicity). But modern technologies have made it possible to create synthetic materials that are similar in their properties to natural ones and are devoid of many of their disadvantages. Modern synthetic material dries quickly, practically does not wrinkle and is able to maintain a decent look for a long time, even with very frequent washings. At the same time, it "breathes" and is pleasant to the skin. You can read about the characteristics of specific types of natural and synthetic fabrics in the corresponding articles of the section.

Fabric properties

2. Physical properties of fabrics

3. Optical properties of fabrics, color, pattern and color of fabrics

4. Technological properties of fabrics

1. Mechanical properties of fabrics

In the process of use, the main wear of clothing occurs as a result of repeated action of tensile load, compression, bending, friction. Therefore, the ability of the fabric to withstand various mechanical influences, that is, its mechanical properties, is of great importance for preserving the type and shape of clothing and increasing the period of its wear.

The mechanical properties of fabrics include: strength, elongation, wear resistance, crease, stiffness, drape, etc.

The tensile strength of the fabric is one of the most important indicators characterizing its quality .

The tensile strength of a fabric refers to the ability of the fabric to withstand stress.

The minimum load sufficient to break a strip of fabric of a given size is called breaking load. The breaking load is determined by breaking the strips of tissue on a tensile testing machine (Fig. 31). Sample 7 is fixed in clamps 8 and 6. The lower one is

Fig. 31. Universal tensile testing machine

press 8 moves from the electric motor up and down,

the upper clamp 6 is connected to the load arm 5.

When lowering the lower clamp, the sample, stretching, moves down the upper clamp, which rotates the load lever 5, which causes a deflection of the pendulum force meter 4 with the load 9. The force meter, with its stop, mixes the gear rack 11 and rotates the gear wheel /, on the axis of which there is an arrow pointing to weight scale 2 the value of the load acting on the sample.

Under the influence of a tensile force, the sample is lengthened and the distance between the clamps increases. The elongation value is fixed on the elongation scale 3 with an arrow 10.

For testing, cut three strips of fabric along the warp and four strips along the weft so that one is not a continuation of the other. It is important that the width of the strip exactly matches the specified dimensions, and that the longitudinal threads are intact. The width of the strips is 50 mm. The distance between the clamps of the machine is taken for woolen fabrics equal to 100 mm, and for fabrics from all other fibers - 200 mm. The strips are cut 100 - 150 mm longer than the clamping length. In order to save fabric, the method of small strips has been developed, in which a strip of 25 mm width is tested with a clamping length of 50 mm.

Breaking load is calculated separately for warp and weft. The breaking load of the sample along the warp or weft is the arithmetic mean of the test results of all the main or all weft strips.

When evaluating tissue in laboratories, the breaking load is determined and compared with the norms of the standards. For example, the strength of cotton dress fabrics is 313 - 343 N on the basis, 186 - 235 N on the weft, 687 - 803 N on the basis of cotton suit fabrics, 322 - 680 N on the weft, 322 - 588 N on the basis of woolen suit fabrics, on a weft 294 - 490 N. Despite the fact that cotton suiting fabrics have a higher tensile strength than woolen fabrics, they wear out faster during use. This is due to the fact that woolen fabrics have higher elasticity and elasticity.

The tensile strength of the fabric depends on the fibrous composition of the fabric, the thickness of the thread (yarn), density, weave, and the nature of the fabric finish. Fabrics made of synthetic fibers have the greatest strength. Increasing the thickness of the threads and the density of the fabric increases the strength of the fabric. The use of weaves with short overlaps also helps to increase the strength of the fabric, therefore, under all conditions being equal, the plain weave gives the fabrics the greatest strength. Finishing operations such as rolls, dressing, decating increase the strength of the fabric. Bleaching, dyeing lead to some loss of strength.

The elongation of the fabric is determined simultaneously with the tensile strength of the fabric on the tensile testing machine. The increase in the length of the sample at the moment of rupture - elongation at break - can be determined in millimeters (absolute elongation) or expressed as a percentage of the original length of the sample (elongation at).

where / 1 is the initial length of the sample; / 2 - the length of the sample at the moment of rupture. For example, the elongation at break of the calico on the warp is 8-10%, on the weft 10-15%; bumazes on a basis of 4-5%, on a duck 12 - 15%; linen on the basis of 4 - 5%, on the weft 6 - 7%; natural silk fabrics on the basis of 11%, on the weft of 14%; staple fabric on the basis of 10%, on the weft 15%.

Modern tensile testing machines are equipped with graph instruments that record stress-elongation curves.

The breaking load is laid down vertically, and the breaking elongation in millimeters or percent horizontally. Elongation curves give an idea of ​​how the material deforms under increasing load. This makes it possible, for example, to judge how the fabric will behave in the processes of sewing production at loads that are much lower than breaking loads.

Linen fabric, for example, has greater strength than woolen fabric, but due to its low elongation, less energy is spent on tearing it than tearing woolen fabric, which has less strength but greater elongation.

The quality of the tissue is largely determined by the ratio of the proportion of elastic, elastic and plastic elongation of the tissue. If the fabric has a large share of elastic elongation, it wrinkles little, and the wrinkles that occur on the fabric during operation quickly disappear. Elastic fabrics are more difficult to wet-heat treatment, but retain their shape well during wear. If a greater percentage of the total elongation of the fabric is elastic elongation, then the wrinkles that occur when wearing clothes gradually disappear - the clothes have the ability to "hang up". If a large proportion of the total elongation is plastic elongation, then the fabrics are strongly crumpled, the clothes quickly lose their shape, and they appear on the elbows and knees. Bubbles. Such products need to be ironed frequently.

The total elongation of the fabric and the proportion of elastic, elastic and plastic elongation in the total elongation depend on the fibrous composition, structure and finish of the fabric.

Synthetic and pure wool fabrics from twisted yarn, fabrics from textured yarns, dense fabrics from wool with lavsan are the most resilient. Fabrics made from natural fibers of animal origin (wool, silk) have significant elastic elongation, therefore they wrinkle little and gradually restore their original shape. Linen, cotton, viscose fabrics, i.e. fabrics made from plant fibers, have a large plastic elongation, so they wrinkle strongly and do not restore their original shape on their own (without wet heat treatment). Flax has the greatest share of plastic deformation, so linen fabrics are crumpled more than others.

The composition of the mixtures and the percentage of fibers of different origin in them affect the elasticity of the fabric. For example, the addition of staple viscose fiber to wool reduces the elasticity of the fabric, the addition of staple lavsan or nylon, on the contrary, increases the elasticity. To increase elasticity, up to 67% of lavsan is introduced into the composition of linen fabrics in the form of staple fibers or multifilament threads. The use of elastic or spandex yarns in the warp and weft systems makes it possible to obtain materials with a three-dimensional structure, which have high elongation. For example, for sports trousers, a fabric with a base made of elastic is produced, which ensures good stretch of the fabric during exercise and preserves the appearance and shape of the product after repeated workouts. The use of elastic as a weft in swimwear fabrics makes it possible to obtain products that fit the figure tightly and do not restrict movement during swimming. High quality corsetry is made of spandex threads.

With a homogeneous fibrous composition, the elasticity of the fabric will depend on its structure, i.e., on the thickness and twist of the threads (yarn) and the density of the fabric. An increase in these indicators increases the elasticity of the tissue.

The ratio of disappearing and remaining elongations depends on the magnitude and duration of the tensile force. With an increase in the load and its duration, the proportion of remaining elongations increases. With prolonged wear, repeated loads lead to the accumulation of irreversible deformation, as a result of which the product loses its shape more and more.

The elongation of the fabric affects all stages of the sewing industry. When creating a model and developing a product design, it is necessary to take into account the percentage of elongation and the ratio of disappearing and remaining elongations. Tapered sleeves, tight skirts and trousers, etc., should be avoided for models made of fabrics that do not have elasticity.

When laying elastic fabrics, the webs should be laid without tension. Stretching the fabric in the flooring reduces the size of the parts. The fabrics stretch especially strongly along the oblique thread, that is, at an angle of 45 ° and close to 45 °. Therefore, when laying, it is necessary to ensure that there is no distortion of the fabric, displacement and sliding of the fabrics in the flooring. With distortions of the fabric and displacement of the fabrics, the shape of the cut details is distorted. When sewing oblique cuts, the fabric is strongly stretched, the direction of the stitching is distorted, which spoils the appearance of the product. Stretching of the upper and lower webs and displacement of parts can occur. With wet heat treatment, by forcibly stretching the fabric (pulling), the product is given a certain shape. At the same time, unwanted stretching of the parts can occur, which leads to damage to the product.

To reduce the stretching of the fabric, a low-stretch linen tape (edge) or a low-stretch fabric with an adhesive coating (adhesive edge) is laid along the edges of the sides of the outerwear. The hem is laid in the armholes of the sleeves, along the waistline and in other details of men's and women's suits. To preserve the shape of the pockets, strips of cotton fabric (lobules) are laid.

Crease - it is the ability of the fabric to form wrinkles and folds during folds and pressure, which are eliminated only with wet heat treatment. The cause of wrinkling is plastic deformation that occurs in the tissue under the action of bending and compression. Fibers with a significant proportion of elastic and elastic elongation, after bending and compression deformation, more or less quickly straighten and take their original position, so the wrinkles disappear.

Crease depends on the fiber composition of the fabric, the thickness and twist of the threads, the weave, the density and the finish of the fabric. The fabrics made from elastic fibers: wool, natural silk, many synthetic fibers are not crumpled much. Fabrics made from cotton, rayon and especially linen tend to wrinkle. The increase in the thickness and twist of the threads reduces the wrinkling of fabrics. The gradual disappearance of wrinkles in woolen, natural silk and synthetic fabrics is explained by the manifestation of the elastic properties of the fibers, due to which, after bending, the fibers return to their original position. The increase in density prevents the threads from shifting in the fabric when it is bent, so dense fabrics are less wrinkled.

Big influence the finish has an effect on the wrinkle of the fabric... To reduce the crease of cotton, staple, viscose fabrics, anti-crease finishes are used. In the sewing industry, to impart crease resistance and ensure the shape of the product, they produce fornose processing.

Reducing crease can be achieved by changing the structure of the fabric and using different types of twisted yarns. The creation of fabrics of volumetric structures with the widespread use of textured yarns makes it possible to produce a large number of various low-wrinkle and elastic silk fabrics.

The sheen, coloration and design of a fabric can accentuate or visually reduce creasing. Wrinkles and folds are most noticeable on light, shiny, fine satin and twill weave fabrics, such as lining fabrics. It seems that light one-colored fabrics wrinkle more than the same multicolored or printed fabrics. The pattern does not reduce the creasing of the fabric, but makes it less noticeable.

Creasing of fabrics spoils the appearance of clothes and complicates the sewing process. Easily wrinkled fabrics wear out faster, as they experience more friction in places of bends and folds, and also lose strength with frequent wet-heat treatments.

Crumpling of tissues. Can be determined organoleptically by crushing tissues in the hands and in a laboratory way on special devices. There are devices for determining oriented and non-oriented crumpling (device "artificial hand" IR-1, which is used to study the deformability of textile materials in the elbow area of ​​the sleeves under repeated stretching and compression; a device for determining the flexural strength of tissues, designed to establish the angle of bending of tissue in degrees after load equal to 124 bends per minute).

When testing a fabric sample for crumpling, depending on the degree of crumpling, the following assessment is given to it: strongly crumpled, crumpled, slightly crumpled, non-crumpled.

Drape - the ability of the fabric to form soft, rounded folds. The drape depends on the weight, stiffness and flexibility of the fabric. Stiffness is the ability of a fabric to resist shape change. The inverse of stiffness is flexibility - the ability of a fabric to easily reshape.

The stiffness and flexibility of the fabric depends on the size and type of fiber, the thickness, twist and structure of the thread, the structure and finish of the fabric. Low-density fabrics made from fine flexible fibers and lightly twisted yarns are characterized by significant softness and flexibility. Flexible fabrics have good drapery, but require attention when laying and sewing, as they are easily warped.

The bending stiffness of fabrics for household use is determined on a PT-2 device by measuring the deflection of a strip of fabric under the action of its own mass. There are special devices for determining the rigidity and elasticity of artificial leather and film materials.

Artificial leather and suede, fabrics from complex nylon threads and monocapron, from wool with lavsan, dense fabrics from twisted yarn and fabrics with a large number of metal threads have significant rigidity. Weaves with short weaves. Overlapping and finishing increases the stiffness of the fabric. Hard fabrics are poorly draped - they form gentle folds with sharp corners. Rigid fabrics lay well, do not warp when stitching, but at the same time offer great resistance to cutting and are difficult to wet-heat treatment.

The requirements for fabric drape depend on its purpose and product model. To create models of dresses and blouses of a free silhouette with soft Lines, ruffles, ruffles, soft folds, fabrics with good draping ability are required. Models of a strictly straight silhouette and widened downwards should be made of stiffer fabrics with less drape. Fabrics for men's suits and coats may have less drape than dress fabrics, as they are used for straight-cut garments.

Fabrics made from natural silk, woolen crepe weaves and soft woolen coats have good drapery. Fabrics made from plant fibers have less drape than woolen and silk fabrics.

The drape can be determined by various methods. The simplest method for determining drape is a method in which a 400x200 mm sample is cut from the fabric. Four points are marked on the smaller side of the sample: the first point is at a distance of 25 mm from the lateral cut of the tissue, the subsequent ones are every 65 mm. A needle is passed through the designated points so that three folds are formed on the fabric. The ends of the fabric are squeezed on the needle with plugs and the distance L is measured in millimeters, at which the lower ends of the free-hanging tissue sample are spaced. Drape D,%, calculated by the formula

D = (200 - A) 1 00/200.

To determine the fabric drape in all directions, the disk method is used (Fig. 32). From the fabric you-

cut the sample in the shape of a circle and place it on a disc of a smaller diameter. The drape of the tissue is determined depending on the number and shape of the formed folds and on the projection area that the tissue gives when the disc is illuminated from above.

The drape ratio is the ratio of the difference

Rice. 32. Determination of fabric drape by disk method: / - fabric; 2 - projection

area of ​​the sample and its projection to the area of ​​the sample.

Drape coefficient Kd,%, is calculated by the formula

Kd = (So - SQ) 100 / So,

where So is the sample area, mm2; SQ - projected area

sample, mm2.

Draping of artificial fur by the loop method is determined on the DM-1 device.

According to TsNIISHP, the drapeability of the fabric is considered good if the following values ​​of the coefficients are obtained as a result of tests. For woolen suits, coats and cotton fabrics, the drape is more than 65%. And for woolen dress fabrics - more than 80%, for silk dress fabrics - more than 85%.

Wear resistance tissues called their ability to withstand a number of destructive factors. clothing, the fabric is exposed to light, sun, friction, bending, compression, moisture, sweat, washing, etc.

A complex complex of mechanical, physicochemical and bacteriological effects leads to a gradual weakening, then to the destruction of tissue.

The nature of the effects experienced by the fabric during use depends on the purpose of the product and the operating conditions. For example, linen wears out from repeated washings, window curtains and curtains lose strength from the action of light, sun; wear on outerwear is mainly due to friction. In the early stages of abrasion, pilling is observed on many textiles.

Pilling is the process of formation of lumps of rolling fibers on the surface of textiles - pills that arise in areas experiencing the most intense friction and spoil the appearance of the product.

Textile materials can be pilled during the manufacture of garments, their use, washing, dry cleaning. The scheme of the appearance and disappearance of pills is as follows: the exit of the ends of the fibers to the surface of the materials, the formation of mossiness; pill formation; separation of pills from the surface of materials.

Fabrics, knitwear, nonwovens containing short fibers, especially synthetic ones, have the greatest pilling properties. Of the staple fibers, polyester fibers provide the greatest pilling. Cotton weft fabrics give more pilling than rayon weft fabrics.

Pilling resistance is especially important for lining materials. Determination of pilling in textile materials is carried out using devices of various designs, called a pilling tester. Depending on the number of pills on an area of ​​10 cm, materials are divided into non-pilling, low-pilling (1 - 2 pills), medium-pilling (3 - 4 pills) and high-pilling (5 - 6 pills).

Under the action of friction, the destruction of the fabric begins with abrasion of the bends of the threads protruding onto the surface of the fabric, forming the so-called support surface of the fabric. Therefore, the abrasion resistance of the fabric can be improved by increasing the supporting surface of the fabric. This is achieved by using weaves with elongated overlaps. All other things being equal, satin and satin weave fabrics have the highest abrasion resistance. Therefore, most lining fabrics are produced in satin and satin weaves.

When cutting, it is necessary to take into account that the destruction of the fabric occurs more slowly if the abrasion is directed along the threads that form the front cover.

During the operation of the products, the fabric is wiped along the bottom of the sleeves and trousers, on the elbows, knees, collar. To increase the wear period of products at the bottom of the trousers, it is recommended to sew on a nylon tape with a rim, which prevents abrasion of the fabric. A braid can be sewn along the side line, collar flare and the bottom of the sleeves in women's products, which serves as an ornament and at the same time prevents wear. Elbow and knee pads are made in sportswear and workwear, which increase the durability of the products.

The highest abrasion resistance is possessed by nylon fabrics and fabrics with an attachment of synthetic fibers. Therefore, to increase the abrasion resistance, staple synthetic fibers are added to woolen fabrics. So, investing 10% of staple nylon fibers in woolen fabric increases its abrasion resistance three times.

It should be remembered that a violation of the mode of wet-heat treatment of tissues - excessive heating and duration of processing - leads to a decrease in the wear resistance of the tissues. In areas of woolen fabric with barely noticeable opal, the strength and wear resistance of the fabric are reduced by 50%.

Under the action of repeated stretching, compression, and twisting, the structure of the fabric and threads loosens. Plastic deformations accumulate in the product, fabrics stretch, and products lose their shape. The fibers gradually fall out, the thickness and density of the fabric decrease; the tissue is destroyed.

The resistance of a fabric to repeated mechanical stress is called endurance. Each tissue has a limit of endurance, after which irreversible changes appear and accumulate in the tissue.

Durability the product increases if, during the operation of the fabric, the load on it does not exceed its endurance limit.

Due to the fact that the wear of clothing occurs as a result of a complex complex of environmental influences and depends on the operating conditions, a single method for determining wear resistance has not yet been established. The durability of new sewing materials can be determined by trial wear. A batch of products is sewn from the materials to be tested, which are handed over to a certain group of people for experimental wear. After a specified time period, the products are examined in organizations conducting experimental wear, the reasons leading to wear are analyzed, and the question of the expediency of "introducing new materials into mass production is decided.

In laboratory conditions, individual factors or complexes of factors are determined that lead to the wear of the fabric: resistance to abrasion, washing and dry cleaning, resistance to repeated stretching and bending, resistance to light weather.

For a versatile study of materials for tension, relaxation (resizing) in various environments and at different temperatures, an electronic device is used - a strograph.

The abrasion resistance of fabrics and knitted fabrics can be determined on devices of various designs. But the principle of operation of the devices is the same - the material is subjected to friction against metal surfaces with a notch, on emery bars, on fabric, etc. The device counts the number of revolutions of the abrasive surface when the test material is abraded to holes or after a certain number of strokes of the device, the decrease in the strength of the material is determined. An acoustic method for testing materials without destruction has been developed, based on the dependence of ultrasound attenuation on material wear.

2. PHYSICAL PROPERTIES OF TISSUES

The physical (hygienic) properties of fabrics include hygroscopicity, air permeability, vapor permeability, water resistance, wetness, dust holding capacity, electrification, etc. Requirements for physical properties are determined by the purpose of fabrics and depend on their fibrous composition, structure and finish.

Hygroscopicity is characterized by the ability of a fabric to absorb moisture from the environment (air). The hygroscopicity Wg,%, is the moisture content of the material at 100% relative air humidity and a temperature of 20 ± 2 ° C.

Wg = (M100 -MS) 100 / ms

where m100 is the mass of the material sample held for 4 hours at a relative humidity of 100%; ms is the mass of an absolutely dry sample.

When assessing the hygroscopic properties of textile materials, the characteristic of their actual moisture content is most often used.

Humidity Wf,%, shows the moisture content in the material at the actual air humidity and is determined by the formula Wf = (mF - ms) 100 / ms

where mf is the mass of the sample at the actual air humidity; ms is the mass of an absolutely dry sample.

Hygroscopicity is especially necessary for linen and dress fabrics. Linen fabrics have the highest hygroscopicity in this range. Cotton fabrics, natural lye fabrics and viscose fabrics have good hygroscopic properties. Synthetic, triacetate fabrics have low hygroscopicity, and only vinol fabrics have hygroscopic properties similar to cotton fabrics. Water-repellent impregnations, application of film coatings, a layer of rubber, leave-in finishing agents reduce the hygroscopicity of the fabric.

Breathability - the ability to allow air to pass through - depends on the fiber composition, density and finish of the fabric. Low-density fabrics have good breathability. Thick fabrics, fabrics with water-repellent impregnations, rubberized fabrics do not have or have a low rate of this property.

Water vapor permeability is the ability of a fabric to allow water vapor to pass through. The penetration of sweat vapors occurs through the pores of the tissue. Hygroscopic materials absorb moisture from the surrounding air and transfer it to the environment. Woolen fabrics slowly evaporate water vapor and regulate the temperature of the warm air better than others.

When creating a model and developing a structure, it is necessary to take into account the air permeability and vapor permeability of materials.

Heat-shielding properties are especially important for winter fabrics. These properties depend on the fiber composition, thickness, density and finish of the fabric. Wool fibers are the most "warm", flax fibers are "cold".

Ticket number 6 (1) Mechanical properties of fabrics

Mechanical properties determine the ability of tissues to resist mechanical stress (stretching, bending, friction, etc.). The main mechanical properties of fabrics include: strength, elongation, crease, drape, wear resistance.

1. Strength – the most important property affecting the quality of the fabric. It is characterized by ultimate tensile strength (characterized by breaking load on the warp and on the weft), tearing and bursting. The stronger the fiber, the thicker the yarn, the denser the fabric, the greater the strength of the fabric. Plain weave gives the highest tensile strength to fabrics. Finishing processes: boiling, bleaching, dyeing - reduce strength; processes - mercerization, dressing, roll - increase strength.

2. Elongation- an increase in the length of the fabric when it is stretched. Determined by tensile testing of fabric on a tensile machine. Elongation at break is the ratio of the absolute elongation at break of a specimen to its initial length, expressed in%. Elongation at break (absolute and relative), as well as breaking load, is a standard measure of fabric quality. The greater the elongation of the fibers, the twist of the yarn, the density of the fabric, the curvature of the threads, the greater the elongation.

Full lengthening of the tissue consists of 3 terms: elastic (disappears immediately after removing the load), elastic (disappears gradually), plastic (does not disappear, remains in the tissue). With a large proportion of elastic elongation in full elongation - fabrics with high elasticity (not wrinkled - made of synthetic fibers). With a high proportion of elastic elongation, the fabrics are quite elastic (low wrinkle - made of wool, natural silk). With a high proportion of plastic elongation - fabrics with low elasticity (highly wrinkled - cotton, linen, viscose).

3. Crease- the ability of tissues to form wrinkles and folds under the influence of bending and compression deformations.

Crumpling mainly depends on the fibrous composition, on the ratio of elastic, elastic and plastic elongation in the total elongation of the tissue (see p. 2)

4. Draping- the ability of the fabric to form soft rounded folds when draping the material. Depends on the softness (stiffness) of the fabric. Softness is the ability to succumb to shape change, rigidity is the ability to resist shape change. Soft fabrics drape better, hard fabrics worse. The softest fabrics are woolen, made from natural silk; the toughest are made of synthetic fibers. Dress and blouse fabrics are draped better than others.

5. Wear resistance- the ability of the fabric to withstand the action of destructive factors: mechanical (friction), physicochemical (light, moisture, temperature, sweat, detergents for washing, solvents for dry cleaning, etc.), biological (the action of microorganisms, decay processes, damage to wool moth). The wear resistance of the fabric depends on the fibrous composition, the type of threads, the type of weaving, the nature of the finish. Moisture does not have a harmful effect, but it promotes the development of microorganisms that damage the fabric. The sun's rays weaken the fabric, especially after washing. Friction is the main destructive factor. The wear of the material appears on the front side, especially on the elbows, knees, along the crotch seams, at the bottom of the trousers, at the edges of the pockets, at the bottom of the sleeves. The wear resistance of fabrics can be increased by using yarns containing synthetic fibers that are resistant to abrasion.

Pilling- the formation of pills on the surface of the fabric - lumps of tangled fibers. Fabrics made of synthetic fibers (nylon, lavsan) are especially prone to pilling. Pilling spoils the appearance of products.

The ability of tissues to resist multiple deformations is called endurance or durability. The first sign of tissue “fatigue” is the garment's loss of shape at the elbows, knees, etc.

The durability of the product depends not only on the wear resistance of the material, but also on the design of the product, its quality, on the constitution of a person and the nature of the wear, on the correct care of the product. The service life of the product can be increased by strengthening individual parts of the garment (with a tape at the bottom of the trousers, lining in the knee area, etc.).

Ticket number 6 (2) Film coated materials, film materials (for waterproof coats and jackets)

Raincoat and jacket materials are intended for the manufacture of clothing that is worn in conditions of high humidity, rains and low temperatures: raincoats, lightweight and insulated jackets, overalls, raincoats, etc.

Requirements for raincoat and jacket materials: water tightness (basic requirement); strength; high abrasion resistance; wind protection; ease ( the surface density of raincoat and jacket fabrics should be in the range of 180-300 g / m 2); slight shrinkage when wet; sufficient air permeability 20-50 dm 3 / m 2. s (the throughput of the fabric for air - in cubic decimeters after 1 square meter per second) - to ensure a comfortable state of a person in clothes; high elasticity; crease resistance; ease of care. They produce 3 types of fabrics: 1 - with water-repellent impregnation; 2 - with polymer coating; 3 - rubberized.

Water-repellent fabrics produce cotton, silk, blended.

Water-repellent impregnation is based on enveloping the fibers with a film that is impervious to water, but permeable to air. To give the tissues water-protective properties, a paraffin-stearin emulsion or organosilicon compounds are used. The fabrics treated in this way almost completely lose their ability to be wetted with water, do not absorb it, do not get wet, and at the same time retain high hygienic properties. Their appearance is improved: they acquire softness and resistance to various stains. Fabrics treated with organosilicon compounds dry quickly after washing, and their protective properties do not decrease after prolonged wear.

Film coated fabrics produced from nylon or lavsan threads with plain or twill weave. For film coating, synthetic resins (polyamide and polyester) and silicones (increasing the surface density by 15 - 20 g / m²) are used. These fabrics have high tensile strength and abrasion resistance, low surface density (70 - 120 g / m²), high water resistance and beautiful appearance. The disadvantage is air tightness, therefore, in the manufacture of raincoats, design features should be provided for air access to the human body (nets, holes). It is necessary to use structures with a minimum number of seams. Cutting of film-coated raincoat fabrics is difficult due to their ability to slip. Making raincoats from these fabrics does not cause any difficulties. For sewing, cotton sewing threads No. 60 and lavsan threads No. 22L and ЗЗЛ and needles No. 85 - 100 are recommended. Products are not subjected to damp heat treatment. Volumetric shapes of products are created in a constructive way.
Rubberized raincoat fabrics are produced on the basis of cotton fabrics or fabrics from artificial or synthetic threads. A layer of a gasoline solution of synthetic rubber or a layer of a latex coating with fillers and pigments is applied to the seamy side or the front side of the fabric and vulcanized. The surface density of the rubber coating is 110 - 190 g / m². Rubber and latex coatings make fabrics waterproof and abrasion resistant, but impermeable to air, so their hygiene properties are poor.

Examples of modern raincoat and jacket fabrics:

Taffeta fabric (Taffeta) - a fabric made of polyester (lavsan) fibers, more durable and more resistant to ultraviolet radiation than nylon (nylon), practically does not stretch when wet. Protects from wind, dries quickly, provides good air exchange. Used for sportswear, jackets, awnings, etc.

Taslan fabric - durable fabric with a dense two-diagonal structure of weaving of fibers and water-repellent impregnation. Reinforcing threads are woven in the longitudinal and transverse directions, which makes the fabric highly resistant to tears, friction, and multiple bends. Due to additional polypropylene processing, the fabric retains its original properties and appearance for a long time. Water repellent, windproof, breathable.

Lacquered fabrics - made of nylon or lavsan, with water-repellent impregnation, with a shiny (glossy) surface, which is formed when finishing on special calenders; Water repellent, windproof, breathable.

Cloak fabric with lacquered finish resembles Bologna fabric

Different requirements are imposed on fabrics for various purposes, that is, they must have appropriate consumer properties. So, linen fabrics must first of all have good hygienic properties: hygroscopicity, moisture absorption, steam and air permeability; fabrics for winter clothing - high heat-shielding properties; lining fabrics - to be smooth, soft, have high abrasion resistance, good hygienic properties, including low electrification; furniture and decorative fabrics - have high artistic and aesthetic indicators, while furniture fabrics also have high wear resistance, and decorative fabrics - resistance to light, good drape (low rigidity).

The consumer properties of fabrics are characterized by certain quality indicators, which are controlled both at the stage of development and at the stage of production of fabrics. In the first case, a wider range of indicators is determined, in the second - those of them that can change as a result of a violation of the technological process. Quality control of manufactured fabrics is carried out according to the compliance of individual quality indicators with the standards of technical specifications.

The consumer properties of fabrics can be conditionally divided into the following groups: geometric; properties that affect the life of the fabric; hygienic; aesthetic.

Geometric properties include: length, width and thickness of fabrics.

The length of a piece of fabric ranges from 10 to 150 m. Due to the fact that unacceptable defects are to be cut out when sorting out the fabric, their number is limited in the standards, which is linked to the establishment of the minimum length of a piece. If the length of the cut is less than the minimum, then it is transferred to a measured flap.

The width of fabrics, different in raw material composition and purpose, ranges from 40 to 250 cm. It is measured in three places at approximately the same distance from each other. The arithmetic mean of three measurements, calculated to the nearest 0.1 cm and rounded to 1.0 cm, is taken as the width of the fabric in a piece.

The thickness of the fabric is taken into account when preparing the flooring (folded in several layers of fabric), along which the fabric is cut. Depends mainly on the thickness of the threads used, the type of weaving and finishing. In turn, the thickness affects such properties of the fabric as heat-shielding, steam, air permeability, etc.

Properties affecting the service life of the fabric are especially important for linen, lining, furniture fabrics, for work clothes, etc. They are also of great importance for the range of clothing fabrics.

The properties that affect the life of the fabric include the following:

Tensile strength is one of the main indicators that determine the service life of a product, although the product is not subject to direct rupture during operation. This indicator is characterized by breaking load (Pp) - the greatest force that a test strip of fabric can withstand when it is stretched to rupture. Measured in N (Newtons).

The stretchiness of the fabric and the stability of the products are characterized by the elongation of the fabric at break.

Abrasion resistance is one of the main properties by which the wear resistance of a fabric can be predicted. Determine the abrasion resistance of the fabric along the plane (lining, linen), or along the folds (shirts, suits, coats), or only pile (pile fabrics). This indicator is assessed by the number of cycles (revolutions) of the device until the complete destruction of the tissue or abrasion of its individual threads.

Shrinkage, or change in dimensions after wet and heat treatments, is a property of a fabric that is taken into account when sewing a product when it is made from the same fabric and when it is sewn from different fabrics.

By the amount of shrinkage, fabrics are divided into non-shrinking, when shrinkage along the warp and weft is up to 1.5%, low-shrinkage - along the warp up to 3.5%, weft up to 2.0%, shrinkage - up to 5 and up to 2.0%, respectively. ...

Light fastness This property is especially important for assessing the quality of fabrics exposed to prolonged exposure to light. Evaluate fabrics for the loss of strength of test strips after exposure to light for a specified time.

Hygienic properties are essential for almost all clothing and linen fabrics. For linen, summer dress, blouse, shirt fabrics, hygroscopicity, vapor and air permeability are more important, for winter - heat-shielding properties, for raincoats - water resistance.

Hygroscopicity - the property of a fabric to absorb and release water vapor from the surrounding air environment. The more moisture is absorbed by the fabric, the more hygroscopic it is. This indicator is determined by the mass of absorbed moisture relative to the mass of dry tissue and is expressed as a percentage.

Permeability is the ability of a fabric to transmit water vapor (sweat), air, sunlight, etc. When assessing the quality of fabrics, indicators such as air and vapor permeability are taken into account. These properties are important for shirts, blouses, dresses and others, especially those used in the summer, fabrics, as well as for all fabrics of the children's range.

Water resistance is the ability of a fabric to resist the penetration of water through it. This property is especially important for assessing the quality of raincoat fabrics. To make raincoat fabrics waterproof, they are subjected to a waterproof or water-repellent finish.

Heat-shielding properties are the ability of a fabric to protect the human body from the adverse effects of low ambient temperatures. If the fabric in the product does not retain heat, then the temperature in the underwear space will drop. Based on this, the heat-shielding properties are assessed by the temperature drop when the heat flow passes through the tissue sample.

Electrification - the ability of a fabric to form and store static electricity. It was found that during electrification as a result of friction, positive or negative charges (of different polarity) can arise. Positive charges are not perceptible for the human body, and the negative ones, which are inherent in synthetic tissues, have an adverse effect on a person.

The mass (surface density) of the tissue affects human fatigue. And it is no coincidence that in recent years, light winter clothing made of quilted fabrics with insulating material (synthetic winterizer, down-feather) has been very popular.

The mass of the fabric affects the wear resistance, heat-shielding and other properties.

Aesthetic properties are of great importance. Their role is great for all household fabrics without exception. When choosing a fabric, the buyer first of all pays attention to its appearance.

Such aesthetic properties as color fastness, crease resistance, rigidity, drapeability, spreadability, pilling ability are determined by laboratory methods, and artistic and coloristic design, fabric structure and its final finishing are determined only visually (visually).

Color fastness is the ability of a fabric to retain color under various influences (light, washing and ironing, friction, sweat, etc.). When assessing the quality of the fabric, the color fastness is determined to those influences to which the product is exposed during operation. This indicator is estimated in points according to the degree of lightening of the initial color of the fabric and according to the degree of coloring of the white material. In this case, 1 point means low, and 5 points - a high degree of color fastness. Depending on the degree of color fastness, fabrics are subdivided into three groups: ordinary - "OK", durable - "PC" and especially durable colors - "OPK".

Crease resistance is the property of a fabric to resist the formation of folds and wrinkles and to restore its original shape after crushing.

Drapery - the ability of a fabric in a freely suspended state to be located in folds of various shapes.

Spreadability is a property of the fabric, which manifests itself in the displacement of the threads under the influence of various loads during the operation of the product. Spreadability is a property that is undesirable for the fabric and negatively affects the appearance of the product.

Pilling - the tendency of a fabric to form pills on its surface as a result of various abrasive effects when wearing a product. Pillies are rolled fibers in the form of balls, braids of various shapes and sizes. As well as expandability, this property manifests itself only during the operation of the product and negatively affects its appearance.

The artistic and coloristic design of the fabric is assessed visually by its artistic expressiveness, originality, novelty, the correspondence of the range of colors and patterns to the fashion direction.

Assessment of the quality level of fabrics. Assessment of the level of product quality includes:

assessment of artistic and aesthetic properties;

assessment of defects in appearance;

assessment of physical and mechanical properties;

assessment of chemical properties.

The artistic and aesthetic properties of fabrics are assessed using an expert method.

Physicomechanical and chemical properties are assessed by laboratory methods.

The assessment of the quality level for the presence of defects in appearance is carried out by examining the fabric from the front side on a rejection table or a forging machine. Defects in the appearance of fabrics occur at various stages of their production and are caused by defects in raw materials and violations of technological processes of spinning, weaving and finishing.

Distinguish between common and local defects. A widespread defect is present along the entire length of the tissues, and local defect is present in a limited area.

Gross local blemishes in pieces of fabric destined for trade organizations are not allowed. These include: holes, under-blinds, spots larger than 2 cm, etc. These defects are cut out at a textile company. If the size of the defect does not exceed 2 cm, the tissue is cut at the site of the defect.

Air permeability- the ability of the fabric to pass air, characterized by the coefficient of air permeability (dm 3 / (m 2 · c), which shows how much air passes through a unit of area per unit of time at a certain pressure difference on both sides of the material.

Endurance- characterized by the number of cycles of multiple deformations that a tissue sample can withstand until fracture. Determine endurance on pulsators.

Geometric properties of fabric- characterize its dimensions - thickness, width, length, on which the rigidity, heat-shielding properties, drape, strength depend

Draped fabric- the ability to form folds and lines under the influence of its own mass.

Left thread twist- the turns when twisting the thread are directed from bottom to top to the left, denoted by the letter S (for silk fabrics - Z).

Linear density of the thread (tex)- an indirect characteristic of the thickness of the thread, which is determined by the value of the mass of the thread with a length of 1 km. The thicker the thread, the greater the linear density.

Mechanical properties- characterize the ability of fabrics to withstand applied mechanical loads (tension, compression, friction, etc.). Under the action of mechanical forces, the material is deformed, its dimensions, shape, thickness, etc. change.

Frost resistance- the ability of a fabric soaked in water to withstand alternating repeated freezing and thawing without deterioration in strength or without visible signs of destruction.

Metric thread number- characterizes the number of meters of thread in one gram. The thinner the thread, the larger the number.

Felling of tissue- Loss of individual threads from open sections of the fabric.

Pillability- characterizes the tendency of the fabric to form pills on the surface (rolled fibers in the form of balls of various shapes and sizes). Evaluated by the maximum number of pills per 10 cm 2 (for woolen ones - per 1 cm 2).

Density of fabric- expressed by the number of main (P 0) and separately by the number of weft (P y) threads located in a certain area equal to 100 mm. The density of fabrics for various purposes is not the same, it can be changed during the production process by changing the fineness of the yarn and weave used.

Surface density of fabric (g / m 2)- the mass of one square meter of fabric, expressed in grams.

Right twist of thread- the turns when twisting the thread are directed from bottom to top to the right, denoted by the letter Z (for silk fabrics S).

- the greatest force withstand until rupture by strips of fabric of a certain specified width (test strip), expressed in kilograms (kgf) or units of force - newtons (N) or decanewtons (daN); 1daH = 10H = 1.02 kgf.

Twist degree- a measure of the intensity of the twist of the threads, which determines the appearance and properties of fabrics. A twist is characterized by the number of twists (turns) per 1m of thread. Distinguish between flat twist (weak 100-200 cr / m), muslin (average 600-800 cr / m), crepe (high 1500-2000 cr / m), mooskrep (the thread consists of two gentle and crepe twists).

Abrasion resistance- the ability of the fabric to withstand abrasion. Evaluated by the number of cycles (revolutions) of abrasion to destruction of the material.

Thermal insulation of fabric (° С / (m 2 · W)- characterized by total thermal resistance, which affects its ability to retain heat. Determined by the decrease in temperature when a heat flow of 1 W passes through 1 m 2 of material.

Toucher (fr. Toucher - to touch, touch)- organoleptic characteristic of the fabric, determined by touch (fabric made of fine wool - elastic and soft, half-woolen with synthetic fiber - hard, crepe de Chine made of natural silk - silky, creaky, etc.)

Elongation at break (elongation at break)- the increment in the length of the stretched test strip of fabric until the moment of rupture, expressed as a percentage in relation to the clamping length of the test strip.

Shrinkage of fabric- change in dimensions as a result of washing, which is defined as the ratio of the difference in dimensions between the marks of the samples after washing to the original size between the marks before washing. Determined separately for warp and weft and expressed as a percentage.

Fatigue of fabric- a gradual local change in the structure of the tissue, not accompanied by a noticeable loss of mass.

Width of fabric in a piece- the distance between the two edges of the fabric with or without edges in the direction perpendicular to the warp threads.

Electrification—The ability of tissue to generate and store static electricity when rubbed. They are characterized by specific surface electrical resistance (Ohm).

SIMULATION THEORY

THE CLOTH

The fabric is made on a loom from two mutually perpendicular threads: the main thread, which runs along the fabric, and the thread, located across the fabric. The number of weaving patterns is very large. The main weaves are as follows:
simple, or smooth (linen, twill, satin, satin); finely patterned (matting, reinforced twill, diagonal, crepe); complex (double, pile, openwork);
large-patterned, or jacquard (fabrics with large patterns in the form of patterns of flowers, etc.).
There has long been a relationship between the form of clothing and the fabric from which these clothes are sewn. So, in the XVI-XVII and partly in the XVIII centuries. produced very dense, heavy fabrics (cloth, velvet, kamlot, brocade, etc.). They matched the complex and unwieldy costumes of those times. At the end of the eighteenth century. the character of a woman's costume changes dramatically, heavy frame forms disappear, clothes with soft draperies come into fashion (the influence of antique costume affects) (Fig. 117, a). draperies are beautiful on soft, light dyed fabrics, when each fold gives deep light and shade. Naturally, the texture (structure) of the fabric changes; there are muslin, muslin, batiste, cashmere, mostly in light colors. Percale (cotton fabric) and linen fabrics are in vogue.
By the 30s of the nineteenth century. in the suit, the clarity of forms begins to appear again; light tissues are replaced by more rigid, although less cumbersome and heavy than before (Fig. 117, b). These are moire, taffeta, reps, poplin, atlas, capaus, etc.
Since each certain period of time is characterized by new lines, silhouettes, cut, new technology, this often results in the emergence of new types of fabrics with new texture and technological properties, because a model of a coat, suit or dress loses all its appearance if it is made of unsuitable or outdated fabrics out of fashion.

Rice. 117

In the textile industry, the production of fabrics from mixtures of fibers of various composition is becoming more widespread - natural wool with silk, wool with staple fiber, silk with cotton and synthetic fibers.
Chemistry played an important role in the creation of a new assortment of fabrics, greatly enriching and expanding the existing assortment. Non-woven, film, duplicated, acetate materials appear.
Fabrics intended for a light dress are soft, elastic, drape well, and form any shape well (dead ends, blouses, summer light coats, etc.). For outerwear, velveteen on foam rubber, pelax on velveteen (men's and women's jackets), rubberized nylon, etc. are widely used.
Methanite and lurex fabrics are designed for fancy dresses. dresses.
The variety of fabrics lies not only in the nature of the weaving of threads, color, pattern. The fabrics are primarily different in their structure. The structure is determined by:
1) the type and thickness of the yarn; 2) the nature of the interlacing of the threads; 3) density. Its thickness, weight, mechanical properties, as well as the type of front surface - texture, depend on the structure and finish of the fabric.
The latter can be very diverse. There are fabrics with a smooth surface (for example, fabrics of satin and satin weaves), with a fleece (drape, cloth), fabrics, as it were, grainy (crepe, sponge, boucle), pile (beaver, velvet, semi-velvet, corduroy rib, corduroy cord ) other.
The surface of the fabric can be shiny, matte, rough, coarse, ribbed, wrinkled, fluffy.

Some fabrics have elasticity and keep well the shape given to them during processing, while others are flabby, loose, easily wrinkled or, conversely, hard, dry, difficult to process.
To get a clearer idea of ​​how the fabric behaves in a particular case, you need to check it on a mannequin or figure and see if it is draped, soft or puffed up in folds and gathers. Only after such a check is it decided whether the fabric is suitable for a particular model.

Dresses, suits and coats with soft lines, deep folds, draperies that emphasize the lines of the figure (Fig. 118, 119) should be made of fabrics such as veils, crepe, georgette, boucle, ratin, which have the ability to drape well.
Fabrics for dresses and summer coats with wide, protruding skirts, stiff draperies, puffy sleeves and large collars (Fig. 120) should be tough, dense (such as taffeta, moire, reps, faye, poplin, pique, embossed satin).
Special mention should be made of transparent fabrics. These fabrics (both natural and synthetic fibers) can be soft and elastic, elastic, stiff and sticky.
The structure of such fabrics is diversified by the use of various metal threads (lurex), as well as by the production itself, reaching ribbing, scaly, crinkling, corrugation, etc.
When deciding the composition of a particular model, taking into account the listed general properties inherent in transparent fabrics, it is necessary, first of all, to reckon with their main property - transparency. That is why draperies, gathers, pleats, flying off tunics (Fig. 121), frills become characteristic elements of clothing here; additions such as scarves, bows, capes, etc. are also typical.
Models made of transparent fabrics should not have a large number of seams, reliefs, lines of yokes, since the latter in this case stand out ugly. You should also not use rigid folds, plastrons (bibs), collars, cuffs and pockets.
The fabric compacted in these details (laid in two or three layers) seems to become heavier, it looks completely different than in the main details.
When making a model from a transparent fabric, it is necessary to provide for a cover. The fabric of the cover should be compatible with the main fabric and not deplete it. Moreover, it is necessary that the fabric of the cover contributes to the identification of the characteristics of the main fabric.
The texture ratios of the cover and the fabric of the dress are important points in the correct solution of the composition.
Sheer fabric can sometimes be duplicated with other fabric. This allows you to make the seams unobtrusive, and the fabric more interesting and advantageous.
Physical and mechanical properties of fabrics
Knowledge of the physical and mechanical properties of fabrics is very important, since in the process of work any fabric is subjected to a wide variety of mechanical influences - stretching, shrinkage, bending, friction.
Extensibility. The fabrics are characterized by tension and strength, and they stretch little along the warp thread, much more along the weft thread, and especially strongly in the oblique direction.
A number of fabrics tend to stretch strongly (artificial crepes, crepe-morocin, pongee, crepe-satin). other fabrics (satin, corduroy, poplin, reps, taffeta, moire) stretch a little.
In fabrics with a large elongation, distortions are possible. Sometimes individual parts of clothing are unevenly stretched, especially in the oblique direction of the threads (coat along the middle waist of the back; folds of the flared skirt in front, back or on the sides; bodice with an oblique arrangement of threads).
When sewing highly stretched fabrics, the edges of the parts to be joined may stretch, the seam gets the wrong direction and spoils the whole look of the product. Most often this is manifested when grinding parts along oblique cuts. When ironing, individual parts from such fabrics can change their shape, the product will be distorted as a result. Therefore, when developing a particular design associated with oblique cuts, it is necessary to take into account the ability of the fabric to stretch. In some cases, it is necessary to pull off the cut parts, leveling and cutting off irregularities.
Products made of fabrics with high elongation and not subjected to special processing (pull-back) lose their shape when finished.
Shrinkage... The property of a fabric to shrink, that is, to partially change the length and width after moistening and wet-heat treatment, is called shrinkage. Fabrics have different shrinkage properties. So, cotton or silk pongee can shrink about 10 -12%, pure wool fabric such as boucle about 8 + 10%, pure wool fabric such as carpetcoat and gabardine - 3 + 5%, staple fabrics - up to 14%. Cotton plaid, braid and satin almost do not shrink.
Shrinkage is beneficial and negative.
The shrinkage that is inherent in pure wool fabrics is considered useful. The composition of woolen fibers includes a cortical layer, which contributes to the creation of a long-term retention of one form or another, achieved in the process of damp-heat treatment. Woolen fabrics differ from others in that they can be stretched (stretch) and reduced (tightened) by means of wet heat treatment in certain areas of the product (by the way, this distinguishes the production of clothes from woolen fabrics from the production of clothes from fabrics of cotton, linen, silk, made of artificial fiber).
Forming products from fabrics that do not have the ability to fit well is much more difficult. In this case, the product has to be given a certain shape exclusively by the design.
Understandable shrinkage refers to the overall excess shrinkage of the fabric by water (rain, washing, cleaning) and damp heat. Therefore, fabrics that have the ability to shrink to one degree or another must undergo preliminary processing - decating, so that the products sewn from them do not deform when worn.
When modeling any product, it is imperative to take into account the fabric's ability to shrink. Often, obtaining the required shape is achieved precisely by wet heat treatment.
Let us give two examples: a jacket with a cut-off barrel made of fabric that is amenable to wet-heat treatment (Fig. 122, a), and a dress with a cut-off barrel made of fabric that is not amenable to wet-heat treatment (Fig. 122, 6). In the first case, the excess fabric along the seam line is crimped, and in the second, it is transferred to a dart.
Another example: if the fabric does not have shrinkage, then the smooth shape of the sleeve is achieved by means of a dart on the sleeve ridge (if there is a top seam of the sleeve, the dart is aligned with it).
Dryness. There are fabrics that have the ability to crumble in sections. This is a negative property. The greatest flowability is characteristic of combed fabrics from coarse and semi-coarse wool, fabrics from rayon and cotton fabrics.
When modeling products from such fabrics, one should avoid the use of undercuts, complex reliefs, yokes, as well as welt pockets, dart loops, gussets in one-piece sleeves. Otherwise, the fabric in the indicated places will creep over time, the product will lose its strength and appearance. In addition, in this case, it is necessary to increase the width of the seams by 1.5-2 times (compared to seams in products made of fabrics that are resistant to shedding) and their overcasting. Hence the additional machining allowances.
Elasticity of the fabric (wrinkle). In the process of wearing, fabrics that do not have elasticity wrinkle easily. Wrinkles and creases appear on various parts of the clothing, causing the clothing to lose its shape and appearance.
This property is determined by the elasticity of the fibers and the structure of the fabric. Woolen fabrics wrinkle a little, as wool is very resilient; on linen, on the contrary, deep wrinkles and folds are quickly formed.
The denser the fabric and the more often the weave, the less the possibility of mutual displacement of the threads (warp and weft) when bending the fabric, the greater its elasticity and less creasing.
Wrinkling of fabric is one of its negative properties. If the fabric is strongly wrinkled, it cannot be used for too narrow, figure-hugging products, draperies, folds, pleats. Such fabrics are not recommended for use in dresses that are not cut along the waist line, especially with a narrow skirt, Sliding fabrics at the seams. This property is typical for fabrics made of natural silk and artificial fiber, for woolen and cotton fabrics (marquise, tussle, reps, matting, pique, poplin, fay). When modeling clothes in the process of compositional development, narrow shapes should be avoided. But in any case, when grinding the details, the seam should be made wider, and the line more often.
Resistant to high temperatures... The fabrics are resistant to high temperatures in different ways. A number of fabrics, for example made of artificial fibers, cannot withstand hot ironing: fabrics are sintered, change color, and significantly shorten in length or width.
When ironing products, one must not forget that too high a temperature and excessively prolonged exposure to the iron on the fabric lead to the weakening of the latter.
Special care should be taken when ironing fabrics containing artificial and synthetic fibers. So, non-observance of temperature conditions in the process of ironing viscose fabrics leads to a change in the color of the fabric, and sometimes to a decrease in strength. When ironing on viscose fabrics, non-liquidable weeds are often formed *; therefore, it is not recommended to use high pressures on the ironing surface.
Dense, dry fabrics are difficult to crimp; the operation must be repeated in this case.
Drawings on fabrics
By the nature of the color, one can distinguish between plain-dyed, printed, multi-colored, mélange fabrics, and according to the pattern, printed and one-colored fabrics with a pronounced weaving pattern.
By their nature, drawings can be of two types.
1. Concise: vegetable (flowers, leaves), thematic (children's, industrial, sports, plot), geometric (stripes, cells, diagonal, polka dots).
2. Abstracted, or pointless (where there is no specific theme of the image).
Each drawing has its own rapport, that is, the repetition of the same theme throughout the canvas. Sometimes the rapport is pronounced, sometimes this repetition is not perceptible. The rapport scale is very different.
* Lasami is the name given to the shiny areas on the fabric that form during the wet heat treatment. When ironing five, the fabrics are flattened, the surface becomes smoother and more shiny. The streamers can be removed from the fabric by steaming, but some of the ironing effect may disappear.
All drawings are divided into:
1) static with vertically and horizontally arranged ornament;
2) different ones, where the diagonal direction of the ornament predominates;
3) combined, combining statics and dynamics.
In addition, fabrics with coupon designs with a border should be highlighted.
The cuff pattern defines its location on the figure. Sometimes it is envisaged to indicate the neckline, armholes, etc.
The kaimovy drawing has wider possibilities for use. Here, the entire canvas is filled with certain, unambiguous forms, repeating throughout the entire canvas, with a gradual increase, where the drawing is concentrated and saturated in the form of a border. The border serves as a trim to accentuate one or more parts of the dress. For example, a border in the center of the dress creates a rich, wide band. In asymmetrically solved compositions, the border strip is placed on one side of the product. Sometimes the border is placed along the yoke line, along the bottom of the skirt, sleeves, etc.
In all periods of fashion, a floral ornament was used in women's clothing. Of course, each period was characterized by its own compositional solutions in the development of drawings of flowers, leaves, branches, bouquets. The location of the rapport, the scale of the drawing, the nature of its application to the fabric changed endlessly. At the same time, sometimes the ornament is depicted in a more naturalistic way, sharply highlighting it against the general background of the fabric. At other times, the same flowers and leaves begin to be depicted in a more conventional, stylized way, they seem to merge with the background of the fabric.
A drawing can have a different background filling: from full filling to rarely scattered forms. Drawings can be with blurred ornaments that merge with the background and resemble the color of the marble surface.
Drawings on fabrics from the point of view of solving the composition are divided into easy and difficult.
These include drawings of small and medium sizes that do not have a top and bottom, as well as large sizes without a pronounced color scheme, with a completely filled background. Here, when solving the composition and when cutting, any line on the fabric can be taken as the central centerline of the product, regardless of the pattern (Fig. 123, a, b). ... In this case, the fabric should be thrown onto the mannequin, pinning it to the right and left so that the drawing is directed in opposite directions (this does not apply to fabrics with a plot and thematic pattern: trees, houses, human figures, etc.), which helps to choose the best solution in the arrangement of the picture.
Large drawings that stand out against the general background are also considered difficult. Fabrics with this kind of pattern should, regardless of the ornament, be used in products of simple laconic forms with a minimum number of seams and reliefs.
In fig. 124, a shows a model of a dress made of fabric with a pronounced dynamic pattern. The scale of the drawing rapport is so large that it fits within one model. The dynamism of the drawing is so pronounced and saturated that the composition is reduced to the simplest and most laconic form without unnecessary seams and reliefs that crush the entire ornament of the drawing.
Drawings in the form of garlands, hair, etc., organized by various elements, must also be considered difficult. Here you need to take into account the size of the picture, its direction, the location of the center line, as well as the general color scheme. The drawing should be located so that it does not visually distort the figure (this happens in cases where a drawing with a bright large ornament is concentrated in the product on the protruding points of the chest, in the hips). When cutting, it is necessary to monitor the coincidence of the pattern on the paired parts in the darts, to maintain the rapport at the joints of the yoke and bodice, bodice and skirt and along the bottom of the product. The drawing should not break off somewhere in the middle.
In fig. 124, 6 show a jumper and a skirt made of fabric with a complex pattern in the form of garlands. The central axial line of the drawing is displaced, which visually distorts the figure. On paired parts (sleeves), the pattern is located in different ways. At the jumper and skirt junction, the pattern is knocked down, the garlands randomly creep one on top of the other; hence the impression of negligence. At the bottom of the jumper, the pattern is cut off in the middle of the rapport.
In fig. 124, c shows the bodice of a dress with a large pattern having a top and a bottom; the color scheme is sharp. The color spots are located so that they are not concentrated in the garment on the most prominent points of the chest. The centerline of the figure is exactly the same as the centerline of the figure. The pattern is symmetrical on both sleeves.
When creating a composition for a particular model, one must remember that on printed fabrics, internal lines, reliefs, wedges, undercuts, small details are hardly noticeable and expressionless. The same can be said for draperies. drapery made on plain dyed fabric that sets off every fold or fold is almost always successful. the drapery made on the printed fabric will be barely noticeable. This is especially true for fabrics filled with small patterns. In this case, only the general silhouette is perceived (Fig. 125).
Before proceeding to the characteristics of individual patterns on fabrics, let us summarize what has been said: when solving a composition from a fabric with a pattern, it is necessary to measure this composition with the scale, size and nature of the pattern in such a way that the latter does not crush, does not knock out the forms and is located so that the figure does not visually deformed.
Pattern "polka dots". This pattern is classic and never goes out of style. Only the size of the peas (small, medium, large) and the rhythmic structure of the pattern change.
There may also be different color ratios between polka dots and background (for example, light polka dots on a dark background and dark polka dots on a light background), depending on
from fashion.
The "polka dot" pattern on the fabric is placed diagonally. When solving a particular composition, this circumstance must be taken into account (in the case of an oblique arrangement of the threads, the rhythm of the pattern is disturbed).
The fabric with the "polka dot" pattern can also be used as a decoration. In that
In this case, the fabric is knocked down, artificially creating a frequent pattern that can be used to decorate the neckline, front of the bodice, the line of the fastener, the frill on the skirt, etc.
Drawing of stripes, cells, diagonals. These fabrics are multi-colored, printed, and also dyed, with a pronounced weaving pattern.
In the compositional solution of various types of clothing, in addition to the properties of fabrics listed above, it is necessary first of all to take into account its pattern. An ill-conceived, indifferent attitude to the drawing often leads to the fact that the fabric, beautiful in a piece, loses all its appearance in an unsuccessfully solved product. It also happens the other way around, when a nondescript-looking fabric is transformed into a well-thought-out composition.
The pattern of stripes, cells and diagonals can play a major role in the compositional solution. Striped and plaid fabrics have won universal acclaim and never go out of style. The severity and geometry of the pattern of these fabrics to some extent limits their use: models with complex draperies or asymmetric solutions are completely inappropriate here.
Each stage of fashion is characterized by different directions of the field and their combination. The longitudinal direction of the pattern on the main parts of the product and the transverse direction on the details (Fig. 126, a) or vice versa (Fig. 126, 6) can be fashionable. There were periods when the stripes were located only in an oblique direction, herringbone (Fig. 126, c).
The simultaneous use of three different directions - longitudinal, transverse and oblique - in one model is not recommended. This splitting of stripes tires the eye, the model looks overloaded (fig. 127).
In included fabrics, first of all, it is necessary to determine the nature of the pattern. If the pattern of cells is symmetrical (in a symmetrical pattern you can find lines of symmetry in the lobar, transverse and oblique directions; Fig. 128, a), then products of any style can be made from such fabric; it is only necessary when cutting to ensure that in paired details the pattern of the cells coincides at the seams, darts, etc.
The pattern is asymmetric, one-sided (Fig. 128, 6) requires special attention, since in a number of models the use of fabric with such a pattern is excluded: at the seams, darts, etc., the pattern will not match.
Printed checkered fabrics, in which the pattern is only on the front side (chintz, garus, flannel), should be used only when creating the most simple models, since such fabrics are very characterized by a skew of the pattern and its mismatch with the weft thread (Fig. 128, c) ... In this case, it is better to replace darts on the bodice and skirt with tucks or gathers (in assemblies, the distortion of the pattern is less noticeable).
To prevent the product from looking sloppy, it is necessary to outline the central centerline of the pattern both on the bodice and on the skirt. If in relation to symmetrical checkered or striped fabric this is not difficult, then in the case of working with fabrics where the pattern is one-sided, asymmetrical, such an operation is most often difficult. Here you need to focus on more noticeable, prominent cells and stripes (it is better to install them by putting the tissue at some distance from you). In fig. 129, and the location of the cells is unsuccessful, the center line of the drawing was found incorrectly; in fig. 1 29, 6 shows the most acceptable option when the central centerline of the drawing is found correctly.
Both on the bodice and on the skirt, fabric with a symmetrical pattern of cells can be positioned so that its direction is oblique. But here, too, it is necessary to correctly outline the central axial line of the drawing; otherwise, the finished product will appear skewed.
It should be remembered that the pattern of stripes or cells inevitably refracts at the points of darts and seams. This is especially noticeable in the area of ​​the upper dart, which runs from the shoulder line, it is impossible to achieve the coincidence of the herringbone pattern, since the bevels of the fabric go at different angles. Accidental refraction of the drawing spoils the product (Fig. 130, a).
In the presence of an upper tuck, it is necessary to ensure that the drawing retains the lobar direction on one side, and on the other, at the armhole, - half-bevel (Fig. 130, 6).
The upper dart can be positioned from the armhole line, and the pattern (stripes or cells) should converge in a herringbone pattern.
The straight direction of the pattern of cells and a smooth combination with the oblique emphasizes the peculiarities of the composition of the model.

Rice. 133

In fig. 131 shows blouse models in which, thanks to darts, a beautiful transition of the pattern from the oblique to the straight direction is achieved.
On skirts of flared cut, there is also a combination of the directions of the pattern: on the sides - a lobe direction, and in front and back - oblique or half-slant, or vice versa. This circumstance must always be taken into account when deciding the form.
It is also necessary to ensure that the pattern of cells (or stripes) coincides along the lines of the seams (Fig. 132, a), otherwise the product takes on a careless appearance (Fig. 132, 6).
It is not recommended to make embossed seams on jackets made of striped or checkered fabrics, along the lines of which the pattern breaks in the most bizarre way (Fig. 133, a). These seams, being the lines of the style, are lost, become invisible, inexpressive, and, in addition, the cell pattern gets confused.
If the jacket is of an adjacent shape, a central seam is made on the back. Along the line of this seam, the strips or cells converge with a herringbone to the waistline, precisely fixing it. Then they keep the forward direction (Fig. 133, 6). It should not be allowed that strips or cells diverge from the waistline with a herringbone.
The decoration of products made from fabrics with a pattern of stripes or cells should be simple and rigorous. Decorations such as embroidery, beading and appliqué are usually not suitable in this case.
Basically, for finishing it is recommended to use plain dyed fabric, leather, felt, braid, buttons, zipper and the same striped or checked fabric, only with a pattern in a different direction (see Fig. 126, a, b and 134).
If the pattern is small or medium, then finishing with a plain-colored inlay or piping can decorate the product and beautifully emphasize its design or small details, especially with the same direction of the pattern on the main part of the product and on the details.
The transition of the shared direction of the drawing to oblique sometimes constitutes the main idea of ​​the composition (see Fig. 131). In this case, it is impractical to supplement the models with various details (pockets, valves); the latter will be inexpressive, they will only violate the entire integrity of the conceived style.

When working with fabrics in a cage and a strip, you need to follow the direction of the pattern, not allowing it to skew.
The pattern of d and gonaley on the fabrics is formed by weaving. If the fabric is one-colored and the diagonals are hardly noticeable, then they can be disregarded when deciding the composition. Multicolored and printed fabrics with pronounced diagonals should be used with caution, since it is very difficult, and often impossible, to achieve the coincidence of the pattern along the lines of seams and darts and the identity of the pattern on paired parts, for greater clarity, we will explain this with a number of examples. So, in a raglan-cut coat, the pattern along the lines of the armholes is refracted differently on the left and right sleeves (Fig. 135, a). Such fabric also looks unacceptably bad if a bodice with one-piece sleeves is sewn from it. Along the lines of the upper seams, the pattern is connected unattractively, and the left sleeve of the product always differs from the right one (Fig. 135, 6). It is impossible to arrange the drawing here more successfully. A jacket or coat with embossed lines - seams also looks ugly: the clarity of the embossed line is disturbed by the fragmentation of the pattern.
It is inadmissible to connect the pattern along the yoke line with a one-piece sleeve (Fig. 135, e), etc.
In fig. 136, a and b show collars - a turn-down and a shawl. The direction of the pattern on both sides of the collars is different. Hence the violation of the rhythm of the drawing, which creates the impression of a production defect.
In fig. 136, c and d shows how the fabric should be positioned (in the oblique direction of the weave threads) in order to achieve the identity of the pattern on the collar flaps. It should be borne in mind that during processing, the ends of the collar are stretched. Their extensibility will not be quite, the same, since on the one hand the transverse direction of the fabric threads prevails, and on the other - the lobe (the extensibility in the transverse direction is greater). Therefore, in order to avoid complex processing when using very stretchable fabrics, it is recommended to make collars from plain dyed fabrics.
The original finishing can be the main fabric with a shared direction of the pattern (fig. 137). This is achieved by cutting the fabrics along the oblique arrangement of the threads. In this case, the asymmetry of the diagonal pattern on the collar is justified, since the pattern seems to continue on the strap to the tie, which gives the model an original look.